Hempblock Extension, Lewes
Our sustainable hempblock design for an extension in Lewes has recently received planning permission.


The client brief was to improve the connection between the kitchen and garden, provide a light filled space for growing plants and an area to sit and relax.
The design is two playful volumes, one with a West facing glass roof to provide daylight for the wall below to grow plants, the other has a green living roof and recessed window seat useable from both sides and when open. Blinds fitted into the timber rafters under the glass roof can be lowered to control glare and light pollution.
The construction is timber frame, hemp insulation, hempblock and wood fibre boards with a lime render. Internally the walls are finished in a light clay plaster.
Heat loss through the glass roof is offset by increasing the insulation in the floors, walls and roof. Other upgrades include internal wall insulation to the main house and the installation of an Air Source Heat Pump.